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r 4.1.1 Soil Analysis Soil sample SB1-1 was analyzed for pH, hydrocarbons and Benzene, Toluene, Ethylbenzene and Xylene (BTEX) utilizing U.S. Environmental Protection Agency (EPA) approved analysis ' methods. Analysis of these samples revealed them to be nondetected to their respective detection limits. A copy of the analysis report, along with Chain-of-Custody documentation for these samples, is included in Appendix A of this report. A copy of the soil boring is included as Appendix B of this report. 4.2 GROUNDWATER MONITORING WELL INSTALLATION On November 22, 1991, IT installed one groundwater monitoring well on the subject property. The well was drilled at the southern extent of the property, directly south of the aforementioned soil boring (see Figure 2). The purpose of this well was to assess possible migration of potential soil and/or groundwater contamination caused by known leaking USTs in the area. Groundwater gradient maps for this site were not available. Because of the close proximity of the Stockton Deep Water Shipping Channel, shallow groundwater was assumed to flow south to north. Based on this assumption, the subject property was determined to be down-gradient of at least one known leaking UST and therefore, it was chosen as the best location to assess the possible groundwater impact. The groundwater monitoring well was installed using a hollow-stemmed auger. This allowed collection of soil samples during the well installation in the same manner as used for the soil boring. Soil samples were collected at five foot intervals down to the completed well depth. The water table was encountered at 12.0 feet below surface at the well location. An OVA was utilized to screen the samples for analysis. Since no readings above background were detected with the instrument, the soil sample collected at the 10 foot interval was submitted for analysis to the PACE Laboratory in Novato, California. 3 WAI M9 I/EES/L7R:0817.IP!